Pushbutton switch construction



Sept- 15, 1 M. E. ANDERSON PUSHBUTTQN SWITCH CONSTRUCTION 2 Sheets-Sheet 2 Filed May 16, 1961 INVENTOR. mam 4R0 E. /4NDER$0N ,4/VOREW K. Fbuz. 05

ATTORNEY United States Patent 3,149,208 PUSHBUTTGN SWITCH CGNSTRUCTION Maynard E. Anderson, Southfield, Mich, assignor to American Radiator & tandard Sanitary Corporation, New York, N.Y., a corporation of Delaware Filed May 16, 1961, Ser. No. 110,583 13 (Claims. (Ci. 200-) This invention relates to pushbutton constructions and arrangements such as are used for example in operating electric switches.

One object of the invention is to provide a multiple pushbutton construction wherein a series of buttons, as for example ten, may be constructed as a unitary one piece plastic molded member, said member being configured so that each of the pushbuttons is capable of independent movement.

Another object of the invention is to provide a multiple pushbutton arrangement wherein the buttons are automatically biased to predetermined operative starting positions when the arrangement is installed on the job, thereby eliminating the need for separate biasing springs for each pushbutton.

A further object of the invention is to provide a multiple pushbutton arrangement which is of relatively low cost, which requires a relatively short time for installation on the job, which can be used in small close quarters, which slides smoothly back and forth when installed, which is not likely to jam or stick, and which has a relatively long service life.

Other objects will be apparent from the following description.

In the drawings:

FIGURE 1 is a sectional view taken through a device having one embodiment of the invention incorporated therein.

FIG. 2 is a top plan view of the PEG. 1 device.

FIG. 3 is a front elevational view of the FIG. l device.

FIG. 4 is a View in the FIG. 1 direction, but taken after actuation of one of the pushbuttons.

FIG. 5 is an enlarged sectional view taken on line 5-5 of FIG. 3, showing a pushbutton structure of the invention prior to its assembly into the FIG. 1 device.

Referring in greater detail to the drawings, and particularly FIG. 1, there is shown therein one portion of an electric apparatus which might for example be a timer for controlling the operation of a domestic washing machine. Insofar as the present invention is concerned, apparatus 10 could have any desired ultimate purpose, the only requirement being that it have a number of devices, such as electric switches, which are required to be operated by pushbutton action.

As shown, apparatus 10 includes a first fiat upstanding front wall 12, two upstanding side walls 14, and a top wall or terminal board 16. Wall 16 is formed of di-electric material, and is provided with printed electrical contacts, two of which are shown at 18 and 26 in FIG. 1. The circuit is completed across each set of these contacts by means of a wire spring element 22, which is constructed and mounted to tend to assume a circuit-closed condition as shown in FIG. 4. Each spring element 22 preferably comprises a U-shaped mounting portion 24, contact-engaging projections 26 and 2.8, a swingable arm portion 27, and a button-engaging actuator portion 30 extending Within a slot 31 of board 16. Each element 22 is installed on wall 16 by initially inserting it through wall opening 32 to engage the edge formed thereby, and then forcing element 22 forwardly to cause nib 34 thereof to snap into a locked position in recess 36 of wall 16. The installation of the various spring elements is preferably accomplished prior to assembly of walls 12 and 16 together.

It will be understood that in practice each complete apparatus may have a large number of wire spring switch elements 22 arranged generally parallel to one another, with each element being designated to cooperate with a different set of contacts 18 and 2G to thereby control the operation of a particular electrical component, as for example a washing machine motor, solenoids for the hot and cold water valves, detergent dispenser, etc. The FIG. 1 apparatus utilizes nine switch elements 22, but the number may be increased or decreased according to the requirements of each particular job.

The operators for the wire elements 22 preferably are made as a unitary one-piece plastic molding 40 formed for example of acetal resin or similar material having characteristics of flexibility and resilience when formed to include thin sections. The unitary plastic member comprises three major portions, namely the base or mounting portion 42, the independently swingable reed portions 44, and the pushbutton portions 46. Mounting portion 42 connects with each one of the reed portions 44, and each reed portion is of relatively thin cross section in a frontto-rear direction (FIG. 1) so that each reed portion is capable of hinging or swinging movement relative to the mounting portion.

Each of the pushbuttons 46 is configured to include a manually-engageable surface 48, a top surface 50 defining a shoulder 52, and an undersurface 54. A downwardly extending portion 56 of each button 46 is arranged to slidahly engage the upper face of wall 16 SO that manual finger pressure on surface 48 causes the pushbutton to slide on wall 16 with a substantially straight line movement. FIG. 1 illustrates one of the pushbuttons in its starting position prior to the application of manual pressure on surface 48, and FIG. 4 illustrates the pushbutton after manual pressure has been applied to its surface 48. In order to facilitate mold-ing of the pushbutton assembly an opening 57 (FIGS. 3 and 5) is formed in the part of each reed portion 44 which aligns with portion 56.

Each pushbutton is molded with a wall portion 58 projecting outward laterally beyond the plane of its side surface 60, and each of the aforementioned switch ele ments 22 has its upstanding actuator portion 30 engaged beneath the inclined surface 62a formed by portion 58. As a result of this arrangement, when the pushbutton is in its FIG. 1 position element 22 is cammed downwardly to break the circuit across contacts 18 and 20; when the pushbutton is in the FIG. 4 position the built-in bias of the spring element moves it to the circuit-closed position.

In order to retain a selected pushbutton in the FIG. 4 position there is provided a movable latch structure 6t), shown in the illustrative drawing as comprising an elongated latch bar 62 having turned cars 64 for swingably mounting the bar on pivot pins 66. As best seen in FIG. 2, the latch bar extends the entire width between side walls 14 so that its front edge 68 overlies each of the pushbuttons. As shown in FIG. 1 front edge 68 is turned down to form a hook portion 70. A tension spring 72 (FIG. 3) may be provided to bias the latch bar downwardly to a position wherein the hook portion 70 is in line with the cam surface 74 of each button 48. In some cases gravity forces may be relied on to operate the latch bar downwardly.

The arrangement of parts is such that during movement of a selected button from the FIG. 1 to the FIG. 4 position surface 74 strikes hook portion 70 to move the latch bar upwardly about pivots 66. As soon as shoulder 52 on the selected button has passed hook portion 76 the tension spring 72 snaps the latch bar downwardly to its FIG. 4 position wherein the selected button is held against movement back to the FIG. 1 position.

It should be noted that when button surface '74 strikes hook portion 70 the consequent raising of bar 62 pemits all buttons but the selected button to automatically assume the FIG. 1 position. The reason for this may best be visualized by a study of FIG. 5, which shows the pushbutton structure in its free state prior to assembly onto wall 12. As seen in FIG. 5, in its free state the mounting portion 42 of the plastic operator has its rear surface 45 located in an imaginary plane passing through the plane of surface 59 of projection 56. When the plastic operator is secured on wall 12 by screws 81 the thickness of wall 12 causes the plastic to be deformed from its free state so as to have a tendency to move the buttons 46 to the right (FIG. 1). Such movement is prevented by engagement between lip iii? of wall 12 and surface 59 of projection 56 so that a built-in bias force is continually exerted on the pushbut'tons. Thus, when latch bar 62 is cammed upwardly by depression of a selected button 48, any other buttonwhich may have been held by the latch will automatically be moved to the FIG. 1 starting position. This action is advantageous in that it permits the user of the apparatus to push a selected button with the assurance that no other undesired button is left in a FIG. 4 depressed condition. The lip 80 forms a stop means for limiting the movement of each pushbutton and establishing its starting position.

In some installations the latch bar pivots 66 may not accurately align with one another or the pushbutton assembly screws may not precisely bear the designed relation to pivots 66, in which eventuality certain of the shoulders 52 may extend upwardly further than others. In order to ensure that in any parts misalignment situation all of shoulders 52 will be capable of being locked by and unlocked from bar 62, each of the shoulder-forming projections is provided with a cam surface 53. The slope of each surface 53 is such that when said surface is engaged by the terminal edge of hook portion 70 there is not enough friction to latch the button in place, i.e., thehook portion must drop down to engage surface 52 before the button is latched.

Referring to FIG. 5, the distance required to move the latch bar between the latching position and the unlatched position is denoted by numeral 55, and the design distance through which the bar is raised on each depression of a pushbutton is denoted by numeral 57. The diiference 59 in dimensions 55 and 57 represents the amount of parts misalignment tolerated by the apparatus. With perfect parts alignment, as pressure is applied on a selected button surface 43 latch bar 62 is raised through distance 57, while any other button which has been latched will spring to the FIG. 1 unlatched position as soon as bar 62 has been raised through distance 55. With imperfect parts alignment, if the initially latched button is higher than the design location by any amount less than distance 59 the button will still be unlatched during depression of the selected button. If the selected button is lower than the design location the bar 62 will of course be raised a distance less than distance 57; this will not interfere with unlatching of the latched button if the bar is raised at least through distance 55 (i.e., if the location of the selected button is off design by anything less than distance 59).

The drawings show the mounting portion 42 and reed portions 44 as exposed, but it Will be appreciated that in practice a surrounding housing (not shown) is usually provided for the apparatus so that only the pushbuttons 46 are exposed. Also, the drawings show each reed portion 44 as having an opening 57 therein. This is done only to permit separation of the mold cavity members used to form the plastic member; openings 57 could be omitted and different type molding procedures used without changing the mode of operation of the plastic member. It will be understood that other changes, modifications and rearrangements could be resorted to without departing from the spirit of the invention as set forth in the appended claims.

I claim:

1. In a multiple switch arrangement, the combination comprising a series of switch elements; an operator for the switch elements comprising a one-piece plastic member forming anelongated mounting base, a series of relatively thin reeds extending at right angles thereto so as to be free for independent swinging movements, and a series of pushbuttons connected with the ends of the reeds remote from the base; and a unitary latch structure arranged in the path of motion of the pushbuttons so thatdepression of any selected one of the pushbutton is effective to first cam the latch structure out of the pushbutton path and then permit it to snap to a position retaining only the selected pushbutton against reverse movement.

2. In a switching arrangement the combination comprising a support structure; a one-piece switch operator mechanism comprising an elongated mounting base fixedly carried by the support structure in generally flatwise relation thereon, a series of reeds extending from the mounting base, and a series of pushbuttons carried on ends of the reeds remote from the base; said mounting base being arranged on the support structure so that the reeds are deformed for thereby biasing the reeds and pushbuttons to a starting position without need for separate biasing springs; stop means rigid with the support structure for resisting the biasing movement and setting the reeds and buttons in their starting positions; and an elongated deflectable latch structure movably mounted to intercept any selected reed-button structure as it is manually moved from its starting position so as to be deflected and then snapped to a locking position preventing reverse movement of the selected reed-button structure; the biased nature of the reeds in their starting positions insuring that only one selected pushbutton will be held in a latched position at any one time.

3. The combination of claim 2 and further comprising means forming a fixed guide surface slidably engaged with the pushbuttons to restrict them to essentially straight line motions as they are moved between their starting and latched positions.

-4. In a device having a series of units to be selectively operated, the combination comprising first and second fixed fiat walls arranged at right angles to one another to form respectively a flat support surface and a flat guide surface, the first wall extending slightly beyond its point of connection with the second wall to form an upstanding lip adjacent the guide surface; a one-piece member defining a fiat elongated mounting base securable to the support surface, a series of independently swingable reeds extending from the base to points beyond the upstanding lip, and pushbuttons connected with the ends of the reeds remote from the mounting base; each pushbutton having a slide surface engaged with the guide surface, a first shoulder on the face remote from the reed, and a second shoulder on the face adjacent the reed to be engageable with the lip to set the respective button in a starting position; and a latch bar swingably mounted to extend adjacent the slide surface so that when any selected button is pushed it slides from its starting position to strike the latch bar, to deflect same and to then permit it to swing back to a position locking the selected button against movement to its starting position.

5. The combination comprising means forming a support surface; a unitary operator construction comprising a mounting portion secured onto the support surface, at least one reed extending from said mounting portion and free of connection with the support surface so as to be free for back-and-forth swinging motion relative thereto, and a pushbutton connected with the reed for moving same; means limiting movement of the button and reed in one direction to establish a starting position therefor;

araaaoe and movable latch means arranged in the path of motion of the operator construction for temporarily holding same in a depressed position after the exertion of manual pressure on the pushbutton.

6. The combination of claim 5 wherein the mounting portion, reed and pushbutton are constructed as a single one-piece plastic molding.

7. The combination of claim 6 wherein the plastic molding is formed in the free state with the support surface-engaging face of the mounting portion located in a plane such that when the plastic molding is installed on the support surface the reed and pushoutton are selfbiased to exert a positive pressure on the aforementioned limiting means, the arrangement being such as to insure location of the button in its starting position when the latch means is moved to a disengaged position. v

8. The combination comprising first and second-walls arranged at right angles to one another to form respectively a support surface and a terminal board; at least two spaced electrical contacts on said board; said board having first and second openings therein arranged adjacent the contacts; at least one electrically conductive spring element having a U-shaped mounting portion located so that its bight is within one opening and its legs are engaged on opposite faces of the board, a contact portion extending from one of the legs into continuous engagement with the first board contact, a swingable elongated arm portion extending from said contact portion, a second contact portion extending from the arm portion into releasable engagement with the second board contact, and an actuator portion extending from the second contact portion through the other board opening so that force thereon is effective to swing the arm portion away from the board to thereby separate the second contact portion from the second board contact; the aforementioned first wall extending beyond the terminal board to form a lip adjacent the other board opening; a onepiece plastic operator for the spring element comprising a base portion secured to the support surface, at least one swingable reed extending from the base portion, and a pushbutton extending from the reed; said pushbutton having a first surface slidably bearing on a surface of the terminal board, a first shoulder normally engaged with the lip to limit movement of the reed away from the support surface, a second shoulder remote from the reed, and a cam surface engaged with the aforementioned actuator portion of the spring element to move same when the reed moves toward the support surface; a swingable latch bar having a latch portion in the line of movement of the pushbutton to be initially de fiected thereby and to thereafter be moved to a latched position engaged with the second shoulder.

9. The combination comprising a terminal board having first and second contacts thereon; an electrically conductive element swingably mounted on the board to alternately bridge and unbridge the space across said contacts; said board having an opening therein, and said element including an actuator arm projecting therethrough so that movement of the actuator arm from one side of the board is efiective to operate the element; a pushbutton mounted to traverse the space adjacent said one side of the board for thereby moving the actuator arm; and latch means operable to releasably retain the pushbutton in one of its limitin positions.

10. The combination of claim 9 and further comprising a mounting means for the pushbutton including a base portion and a swingable reed portion extending between the base portion and pushbutton.

11. In combination, a terminal board having first and second contacts thereon, and an opening adjacent the first contact; a generally U-shaped Wire form switch element having its web portion positioned in the opening and having one of its leg portions engaging the first contact; an extension on said one leg portion arranged to alternately engage and disengage the second contact; and a pushbutton mounted to traverse a portion of said extension for moving same between its engaged and disengaged positions.

12. in combination, a terminal board having first and second contacts thereon, and an opening adjacent the first contact; a generally U-shaped switch element having its web portion positioned in the first opening and having one of its leg portions engaging the first contact; an extension on said one leg portion arranged to alternately engage and disengage the second contact; and a pushbutton mounted to traverse a portion of said extension for moving same between its engaged and disengaged positions.

13. In combination, a terminal board having first and second contacts thereon; an electrically conductive element swingably mounted to alternately bridge and unbridge the space across said contacts; and a pushbutton mounted to move between limiting positions to move the conductive element between its bridged and unbridged positions, said pushbutton being formed of plastic material and being deformed by its mounting so as to be automatically biased to one of its limiting positions without need for a separate spring means.

Bramming Mar. 25, 1919 Scott May 31, 1927 

1. IN A MULTIPLE SWITCH ARRANGEMENT, THE COMBINATION COMPRISING A SERIES OF SWITCH ELEMENTS; AN OPERATOR FOR THE SWITCH ELEMENTS COMPRISING A ONE-PIECE PLASTIC MEMBER FORMING AN ELONGATED MOUNTING BASE, A SERIES OF RELATIVELY THIN REEDS EXTENDING AT RIGHT ANGLES THERETO SO AS TO BE FREE FOR INDEPENDENT SWINGING MOVEMENTS, AND A SERIES OF PUSHBUTTONS CONNECTED WITH THE ENDS OF THE REEDS REMOTE FROM THE BASE; AND A UNITARY LATCH STRUCTURE ARRANGED IN THE PATH OF MOTION OF THE PUSHBUTTONS SO 